Description: An Osprey is silhouetted by the setting sun as it sits high atop a cypress snag on Lake Marion , South Carolina . The Osprey ( Pandion haliaetus ) , also known as seahawk , fish hawk or fish eagle , is a fish eating bird of prey . It is a large raptor , reaching 60 centimetres ( 24 in ) in length with a 1 . 8 metre ( 6 ft ) wingspan .